JPH08170603A - Actuator - Google Patents

Abstract

(57) [Summary] [Purpose] In an actuator using a braided reinforcement hose, to improve the durability due to repeated expansion and contraction. [Structure] A braided reinforcing hose 9 composed of a rubber tube 10 and a fiber reinforcing layer 11 provided on the surface of the rubber tube 10, and sealing fittings 13 and connecting fittings 14 provided at both ends of the braided reinforcing hose 9. An actuator that causes expansion in accordance with a pressurized state inside thereof, and uses the expansion / contraction action of the entire length due to the expansion as an actuating force, and the fiber reinforcing layer 11 is provided only in the mounting portion of the sealing metal fitting 13 and the connecting metal fitting 14. A buffer layer 12 is provided to cover the metal fittings and the fiber reinforcing layer 11 to prevent rubbing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an actuator capable of moving an operating end with a length which changes due to expansion caused by the internal pressure of a tube.

[0002]

2. Description of the Related Art Electromagnetic solenoids, hydraulic cylinders, linear motors, etc. have been conventionally used as typical actuators. However, these may be unsuitable depending on the atmosphere used. For example, if an electromagnetic solenoid or a linear motor is used in a place with high humidity, it is difficult to take measures against insulation and safety measures against electric leakage must be taken. Further, the hydraulic cylinder cannot eliminate the risk of oil leakage, and is not suitable for use in the manufacturing site of precision equipment indoors or for equipment used at home.

However, in recent years, actuators that use neither hydraulic pressure nor electricity have been proposed. Specific examples thereof include the Japan Society of Mechanical Engineers, Volume 57, No. 542 (1991-10), Paper No. An actuator such as the FHA (Hydrolic Actuator) described in 90-1519B. This actuator is a braided reinforcing hose 1 consisting of two layers as shown in FIG. 10, in which a hollow rubber tube 2 (styrene-butadiene rubber or the like is used for its material) is arranged, and this rubber tube is used. 2 has a structure in which a fiber reinforcing layer 3 (a synthetic fiber such as polyester fiber or a natural fiber such as cotton is used as a material thereof) is provided so as to cover 2.

As shown in FIG. 11, the fiber reinforcing layer 3 has a braided reinforcing hose when the inside pressure is applied when the braided angle (turning angle) θ is 54 degrees 44 minutes (this is called a static angle). It is known that the elongation of the rubber tube 2 in the longitudinal direction is balanced with the bulge of the outer diameter of the rubber tube 2 (for details, see, for example, the magazine "Rubber World" 196).
It is stated in the November 8 issue). In a hose for general fluid transportation, fibers are braided at the above-mentioned static angle or a value close to this.

In such a braided reinforcing hose, the braid angle is set to be smaller than 54 degrees and 44 minutes (for example, 30 degrees).
Then, it can be made to act as an actuator that generates a tensile force at the time of pressurization, and can be used, for example, in a drive mechanism as shown in FIG. In FIG. 12,
The fixing member 4 based on the drive mechanism, and the fixing member 4
On the other hand, one end of the actuator 6 using the braided reinforcing hose 1 is attached to the fixed member 4 and the other end is attached to the movable member 5.

As shown in FIG. 13, the actuator 6 has a sealing metal fitting 7 (for closing the end portion of the braided reinforcing hose 1 so that the pressurized medium does not leak) at one end of the braided reinforcing hose 1. It is crimped, and a connecting fitting 8 (for connecting a pipe for conveying a pressurizing medium from the pressurizing device) is crimped to the other end. As shown in FIG. 13, the sealing metal fitting 7 and the connecting metal fitting 8 also serve as mounting metal fittings for the respective members.

If a pressurizing device (not shown) having a pump function is connected to the connecting fitting 8 via a pipe (not shown), the pressurizing medium is supplied into the actuator 6. In contrast to the normal state shown in FIG. 13, when pressurized, it expands as shown in FIG.
This expansion shortens the overall length of the actuator 6,
Further, when the pressurizing medium is collected in the pressurizing device, it is returned to the state of FIG. 13 and the entire length becomes the initial state.

Explaining the operation in FIG. 12, by supplying a liquid (or a gas such as air) under pressure to a hollow portion of the actuator 6 by a pressurizing device (not shown),
The state of FIG. 13 is changed to the state of FIG. 14, and accordingly, the total length of the actuator 6 is shortened. Due to this change in length, the movable member 5 rotates from the dotted line position to the solid line position. In this way, the actuator 6 using the braided reinforcing hose exerts the same function as the hydraulic cylinder, and a sufficient value can be obtained in power.

As a medium for pressurizing the actuator, a petroleum-based (operating oil, machine oil, etc.), alcohol-based (glycerin, polyethylene glycol, etc.) or water, or a mixed system based on these is used. it can.

[0010]

However, since the above-mentioned conventional actuator needs to apply internal pressure, it is necessary to mount metal fittings (sealing metal fittings, connecting metal fittings, etc.) on both ends. However, the braid angle does not change due to the internal pressure in the part of the fiber reinforced layer in contact with the metal fitting, but since the part outside the metal fitting is largely deformed by the internal pressure, the friction generated between the fiber and the metal fitting is repeated, Durable is difficult to obtain.

Therefore, an object of the present invention is to provide an actuator using a braided reinforcing hose, which can improve durability due to repeated expansion and contraction.

[0012]

In order to achieve the above object, the present invention provides a braided reinforcing hose comprising a rubber tube and a fiber reinforcing layer provided on the surface of the rubber tube, and a braided reinforcing hose at both ends thereof. In an actuator that is composed of a metal fitting for connection or sealing that is provided, causes expansion in response to a pressure change of a pressurizing medium introduced into the metal fitting, and uses the expansion / contraction action of the entire length due to the expansion as an actuating force. A buffer layer for covering the fiber reinforcing layer is provided only on the mounting portion of the metal fitting.

For the buffer layer, a rubber material having excellent weather resistance or oil resistance can be used. In addition, the above purpose is
A braided reinforcing hose made of a rubber tube and a fiber reinforcing layer provided on the surface of the rubber tube, and connecting or sealing metal fittings provided at both ends of the braided reinforcing hose. In an actuator that causes expansion in response to a pressure change of a pressure medium and uses the expansion / contraction action of the full length due to the expansion as an operating force, with respect to the braid angle of the central portion of the fiber reinforcement layer, the braid angle of the fitting portion of the metal fitting It is also achieved by increasing.

In this case, the braid angle of the central portion of the fiber reinforcing layer can be set to 15 to 45 degrees, and the braid angle of the metal fitting mounting portion can be set to 45 to 65 degrees.

[0015]

According to the above-mentioned means, the buffer layer provided so as to cover the portion of the braided reinforcing hose to which the metal fitting is attached (fastened) functions as a cushioning material for preventing the metal fitting and the fiber reinforcing layer from contacting each other. Prevent the fiber reinforcement layers from rubbing against each other. Thereby, the durability of the actuator can be improved.

When a rubber material having excellent weather resistance or oil resistance is used for the buffer layer, deterioration of the buffer layer is less likely to occur even when contacting with outside air or oil. As a result, the life of the buffer layer and thus of the actuator can be extended. Further, according to the above-mentioned other means, in the fiber reinforcing layer of the braided reinforcing hose,
By setting the braid angle of the metal fitting mounting portion to be larger than the central portion, the amount of expansion and contraction due to pressurization and depressurization of this portion becomes smaller than that in the central portion, and it is possible to reduce friction between the fiber reinforced layer and the metal fitting. . As a result, the durability of the actuator can be improved.

In particular, when the braid angle of the central portion of the fiber reinforcing layer is set to 15 to 45 degrees, a large contraction force can be obtained and the driving force does not become insufficient even when used as an actuator. And, the braid angle of the metal fitting mounting portion is 45 to
When set to 65 degrees, the static angle (=
The angle value becomes 54 degrees 44 minutes) or in the vicinity, and the friction between the fiber reinforcing layer and the metal fitting is reduced. Therefore, the durability of the actuator can be improved.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. [Embodiment 1] FIG. 1 is a sectional view of a metal part of a braided reinforcing hose of an actuator according to the present invention, and FIG. 2 is a front view showing the braided reinforcing hose of the actuator of FIG.

As shown in FIG. 1, the braided reinforcing hose 9 of the actuator according to the present invention has a three-layer structure. A rubber tube 10 made of nitrile rubber or the like is disposed on the innermost side, and a fiber reinforcing layer 11 in which a polyester yarn is braided at a braid angle of 30 degrees is provided on the surface thereof. Further, as shown in FIG. 2, an outer rubber layer 12 as a buffer layer is provided on the fiber reinforced layer 11 only in a portion where the metal fitting is mounted. The reason why the outer rubber layer 12 is provided only in the fitting mounting portion is that if it is provided in the central portion of the braided reinforcing hose 9, the movement of the fiber reinforcing layer 11 is restrained and the movement of the rubber tube 10 due to pressurization and depressurization is hindered. is there.

For the outer rubber layer 12, it is preferable to use rubber such as chloroprene rubber and chlorosulfonated polyethylene rubber when importance is attached to weather resistance, and rubber such as nitrile rubber and acrylic rubber when importance is attached to oil resistance. it can. A sealing metal fitting 13 and a connecting metal fitting 14 are provided on the surface of the outer rubber layer 12.
When the fittings 14 (both of which may be the connection fittings 14) are attached by crimping, the actuator is completed as shown in FIG. 3 (front view). It should be noted that FIG. 4 is a front view showing a state where expansion is caused by pressurization.

As a method of forming the outer rubber layer 12, for example, after the outer rubber layer 12 is formed by extrusion over the entire area of the fiber reinforced layer 11, cuts are provided on both sides with a cutter or the like, and the rubber between the cut positions is formed. A method of removing can be adopted. The present inventors conducted a test using the actuator described above by alternately repeating the state shown in FIG. 3 and the state shown in FIG. This test is hydraulic 2MP
The test was carried out at 30 times / min with a. As a result, in the conventional actuator having no outer rubber layer, the breakage due to the rubbing of the yarn occurred after about 50,000 times.
Even after repeated driving for 10,000 times, no breakage occurred and it was confirmed that the durability was improved. This can be considered that the outer rubber layer 12 functions as a cushioning material.

[Embodiment 2] FIG. 5 is a front view showing another embodiment of the actuator according to the present invention, and FIG. 6 is a front view showing details of the braided reinforcing hose in the actuator of FIG. This example also aims to prevent friction (rubbing) between the fiber reinforced layer and the metal fitting in the metal fitting portion, and the rubbing can be prevented without providing the outer rubber layer required in the above embodiment. It has features.

The braided reinforcement hose 15 in this embodiment is
It is composed of the rubber tube 10 and the fiber reinforcement layer 11, and the braid angle at the central portion of the fiber reinforcement layer 11 and the braid angle at both ends (mounting parts of the metal fittings) are set to different values. That is, the braid angle at the central portion is 30 degrees, and the braid angles at both ends are 54 degrees and 44 minutes. When the sealing metal fitting 13 and the connecting metal fitting 14 (both ends may be the connecting metal fitting 14) are attached to both ends of the braided reinforcing hose 15 having such a structure by crimping or the like, the actuator shown in FIG. 5 is completed. The state of FIG. 5 is a state before pressurization, and if the inside of the braided reinforcement hose 15 is pressurized in this state, it expands as shown in FIG. 7 and the total length is shortened, resulting in the same driving force as that of the hydraulic cylinder. Obtainable.

FIG. 8 is a characteristic diagram showing the relationship between the braid angle and the contraction force. As is clear from FIG. 8, the contraction force increases as the braiding angle decreases. However, the braid angle is 10
In the vicinity of the degree, there are few intersecting points due to the left and right turning of the fiber, so that the shape retention of the fiber reinforcing layer 11 is difficult. Also,
If the braid angle exceeds 45 degrees, the contraction force becomes small and it is not suitable for use as an actuator. From this fact, the braid angle in the central portion is preferably 30 degrees,
Any other value may be set within the range of 15 to 45 degrees, whereby the contraction force necessary for the actuator can be secured.

On the other hand, the present inventors alternately repeated the state of FIG. 5 and the state of FIG. 7 and measured the durability. At the time of this measurement, the braid angle in the central portion was set to 30 degrees, and the life span between the both ends of the braid angle was 30 to 70 degrees was measured every 5 degrees, and the results shown in FIG. 9 were obtained. As is apparent from FIG. 9, the number of pressurizations is the theoretical value of the static angle of 54 degrees and 44 minutes, and the best result is shown in the range of ± about 10 degrees centering on the static angle of 200,000. No rupture or the like was observed even after reaching the times. From this, it is best that the braid angles at both ends are 54 degrees and 44 minutes, but 45
Within the range of ˜65 degrees, it is possible to prevent a difference in durability.

[0026]

According to the above-mentioned means, a braided reinforcing hose comprising a rubber tube and a fiber reinforcing layer provided on the surface of the rubber tube, and connecting or sealing fittings provided at both ends of the braided reinforcing hose. In the actuator which is constituted by and causes expansion according to the pressure change of the pressurizing medium introduced into the inside, and the working force is the expansion and contraction action of the full length due to the expansion, the fiber is provided only in the mounting portion of the metal fitting. Since a buffer layer covering the reinforcing layer is provided,
Rubbing between the metal fitting and the fiber reinforcing layer is prevented, and the durability of the actuator can be improved.

By using a rubber material having excellent weather resistance or oil resistance for the buffer layer, the life of the actuator can be extended. Further, it is composed of a rubber tube and a braided reinforcing hose made of a fiber reinforcing layer provided on the surface of the rubber tube, and connecting or sealing metal fittings provided at both ends of the braided reinforcing hose, and introduced into the inside thereof. In the actuator that causes expansion according to the pressure change of the pressurizing medium, and uses the expansion and contraction action of the full length due to the expansion as an actuating force, with respect to the braid angle of the central part of the fiber reinforcement layer, By increasing the braid angle, the friction between the fiber reinforcing layer and the metal fitting is reduced, and the durability of the actuator can be improved.

In this case, the durability of the actuator is improved by setting the braid angle of the central portion of the fiber reinforcing layer to 15 to 45 degrees and the braid angle of the metal fitting mounting portion to 45 to 65 degrees. be able to.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a metal part of a braided reinforcing hose of an actuator according to the present invention.

FIG. 2 is a front view showing a braided reinforcing hose in the actuator of FIG.

FIG. 3 is a front view showing the overall configuration of an actuator according to the present invention.

FIG. 4 is a front view showing a state where the actuator of FIG. 3 is expanded by pressurization.

FIG. 5 is a front view showing another embodiment of the actuator according to the present invention.

6 is a front view showing details of a braided reinforcing hose in the actuator of FIG.

FIG. 7 is a front view showing the state of the actuator of FIG. 5 when inflated.

FIG. 8 is a characteristic diagram showing the relationship between the braiding angle and the contracting force of the central portion of the braided reinforcing hose.

FIG. 9 is a characteristic diagram showing the relationship between the braiding angle of the metal fitting mounting (fastening) portion and the number of pressurizations.

FIG. 10 is a perspective view showing an example of a braided reinforcing hose used in a conventional actuator.

11 is an explanatory diagram showing an example of setting a braid angle in the braided reinforcing hose of FIG.

FIG. 12 is a front view showing an example of a drive mechanism to which an actuator using a braided reinforcing hose is applied.

13 is a front view showing a state in which a connecting fitting or the like is attached to the braided reinforcing hose of FIG. 10 to complete an actuator.

FIG. 14 is a front view showing a state where the actuator of FIG. 13 is pressurized and expanded.

[Explanation of Codes] 1,9,15 Braided Reinforcing Hose 2,10 Rubber Tube 3,11 Fiber Reinforcing Layer 4 Fixed Member 5 Movable Member 8 Connection Metal Fitting 12 External Rubber Layer 13 Sealing Metal Fitting 14 Connection Metal Fitting

Claims (4)

[Claims] 1. A braided reinforcement hose made of a rubber tube and a fiber reinforcement layer provided on the surface of the rubber tube, and metal fittings for connection or sealing provided at both ends of the braided reinforcement hose. In the actuator that causes expansion in response to a change in pressure of the pressurizing medium introduced into, and uses the expansion / contraction action of the full length due to the expansion as an actuating force, the braided reinforcement hose includes the fiber reinforcement layer at the mounting portion of the metal fitting. An actuator having a buffer layer that covers the. 2. The actuator according to claim 1, wherein the buffer layer is made of a rubber material having excellent weather resistance or oil resistance. 3. A braided reinforcing hose composed of a rubber tube and a fiber reinforcing layer provided on the surface of the rubber tube, and connecting or sealing fittings provided at both ends of the braided reinforcing hose, and the inside thereof. In the actuator that causes expansion in response to a pressure change of the pressurizing medium introduced into the, and the working force is the expansion and contraction action of the full length due to the expansion, the braided reinforcement hose is a braided angle of the central portion of the fiber reinforcement layer. On the other hand, an actuator characterized in that a braid angle of a mounting portion of the metal fitting is increased. 4. The fiber reinforcing layer according to claim 3, wherein the braid angle of the central portion is set to 15 to 45 degrees, and the braid angle of the metal fitting mounting portion is set to 45 to 65 degrees. Actuator.